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214Chapter 410 Gigabit EthernetTo confirm the high-speed future of Ethernet, the IEEE 802.3ae WorkingGroup has defined two Physical Layer standards for 10 Gbps optical Ethernet.These include a LAN PHY and a WAN PHY. The LAN PHY doesnot differ from the existing LAN standard, whereas the WAN PHY isnew. It specifies asynchronous 10 Gbps transmissions using the traditional802.3 Ethernet frame format, stipulates the minimum and maximumframe sizes, and recommends a MAC scheme at the clientinterface. At 1,550 nanometers, it will initially reach 40 Km, expanded to80 Km in coming months.Currently, 10 Gbps Ethernet is standardized for transport over fiberonly; no copper twisted-pair option is available as there is in Gigabit Ethernet.When the standard was first conceived, little thought was given toa need for that kind of bandwidth to the desktop. However, the need isbeginning to emerge and some chip manufacturers are now planning for10 Gbps Ethernet over copper, using a design that will transmit 100meters without a repeater. Working closely with the standards bodies,this capability will no doubt be reached soon.Ethernet SummarySo why has Ethernet suddenly become such a powerful contender in themetro space? There are numerous reasons. Ethernet has been around fora long time and is understood, easy to use, and trusted. It is a low-costsolution that offers scalability, rapid and easy provisioning, granularbandwidth management, and simplified network management due to itssingle-protocol nature. As its popularity has increased and it has edgedinto the WAN environment, it now supports such applications as largescalebackup, streaming media server access, Web hosting, ASP connectivity,SANs, video, and disaster recovery.VLANs are critically important in environments that require logicalnetwork segmentation, and at Champlain College this has proven to bea major issue—and an advantage. Often characterized as a VPN madeup of a securely interconnected collection of LANs, a number of vendorsnow offer VLANs as a service. TLAN or target LAN server (TLS) serviceshave gained the attention of the industry; they allow multiple LANs to beinterconnected in a point-to-point fashion. An example is shown inFigure 4-23 where we see a company that has multiple locations inter-